| Summary: | This study has investigated the feasibility and advantages of using ternary blended binders containing limestone powder (LP), i.e. Portland-limestone cement (PLC), with fly ash (FA) or ground granulated blastfurnace slag (GGBS) in three types of high-consistence concrete i.e. self-compacting concrete (SCC), flowing concrete (FC) and underwater concrete (UWC), concentrating on the hardened mechanical and durability properties. Initially, mix design methods, tests, target fresh properties and constituent materials were selected for each concrete type. In the first stage of the study SCC mixes were formulated with binary and ternary binder blends with up to 80% cement replacement (by volume). The hardened properties of these, i.e. compressive and tensile strength, sorptivity and rapid chloride penetration resistance, were measured and the relationships between these investigated. Optimum replacement levels of GGBS and FA were estimated (40 and 20% respectively), and were used in the subsequent stages of the study on FC and UWC. The main outcomes were: -It is feasible to produce high-consistence concrete using ternary blended binders with LP and GGBS or FA. -It is possible to achieve similar or higher long-term compressive strengths with ternary binder mixes than with binary binder mixes for concrete with low water/cement ratio (<0.4). -A good relationship was obtained between the sorptivity results and the compressive strength which was independent of the concrete type, age and powder composition. -No relationship between the rapid chloride penetration test results and the compressive strength was obtained; the results had a high degree of scatter. There were reductions in the total embodied carbon contents of the concrete mixes with the incorporation of additions. There is scope for further investigating the synergistic effect between limestone powder and ggbs and fly ash to further reduce the Portland cement content leading to greater potential economic and environmental advantages.
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